His good looks, his personality...Maybe his prowess with a knife? I dunno.

I was really thinking about gameplay perks. Kelly could have a speed boost. Linda could be really accurate with Nornfang. As for Fred... maybe he could have a larger assassination range? That seems like the most feasible gameplay-impacting feature (even though it is rather limited).

I just would have liked your companions' in-game AI to have little quirks that would add to their characters. A feature like this would have really added to games like Star Wars: Republic Commando and Halo 5: Guardians.

Middlefingerstudios:

Kelly's movement speed is actually faster than the others, there's some other alterations, I just don't remember what they are

Really? I've never actually played H5 so I wouldn't know. I do know it was a feature that was sorely lacking from Republic Commando...